While many coolant or lubricant applicators exist in the marketplace, none combine the features of a lubricant applicator having a constant depth reservoir. The combination of components that form the present invention produce a device that has many valuable features not found in the prior art. Known lubricant and lubricant applicators lack the combination of a structure for regulating the lubricant flow rate, a structure for visually ensuring the flow rate, and an apparatus which turns the lubricant applicator off. Additionally, the present invention does not require a pressurized system in order to measure the lubricant.